CA1077019A - Raise drill inner yoke bridge - Google Patents
Raise drill inner yoke bridgeInfo
- Publication number
- CA1077019A CA1077019A CA310,322A CA310322A CA1077019A CA 1077019 A CA1077019 A CA 1077019A CA 310322 A CA310322 A CA 310322A CA 1077019 A CA1077019 A CA 1077019A
- Authority
- CA
- Canada
- Prior art keywords
- raise
- drive stem
- drill
- bit body
- inboard
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 230000035939 shock Effects 0.000 claims abstract description 7
- 230000000712 assembly Effects 0.000 claims description 8
- 238000000429 assembly Methods 0.000 claims description 8
- 238000005096 rolling process Methods 0.000 claims description 5
- 238000009826 distribution Methods 0.000 claims description 4
- 238000012856 packing Methods 0.000 claims description 4
- 238000005553 drilling Methods 0.000 abstract description 6
- 230000006641 stabilisation Effects 0.000 abstract description 4
- 238000011105 stabilization Methods 0.000 abstract description 4
- 238000005452 bending Methods 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000005755 formation reaction Methods 0.000 description 3
- 210000002832 shoulder Anatomy 0.000 description 3
- 229920002635 polyurethane Polymers 0.000 description 2
- 238000010276 construction Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/02—Couplings; joints
- E21B17/04—Couplings; joints between rod or the like and bit or between rod and rod or the like
- E21B17/046—Couplings; joints between rod or the like and bit or between rod and rod or the like with ribs, pins, or jaws, and complementary grooves or the like, e.g. bayonet catches
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/02—Couplings; joints
- E21B17/04—Couplings; joints between rod or the like and bit or between rod and rod or the like
- E21B17/07—Telescoping joints for varying drill string lengths; Shock absorbers
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B7/00—Special methods or apparatus for drilling
- E21B7/28—Enlarging drilled holes, e.g. by counterboring
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Mechanical Engineering (AREA)
- Drilling Tools (AREA)
- Earth Drilling (AREA)
Abstract
ABSTRACT
The Present invention relates generally to raise type earth boring drills and, more particularly to such raise drills having shock elements for absorbing impact type loads passing through the drill.
During a raise drilling operation, a tremendous amount of wear and stress is imposed upon the drive stem of the raise bit. Because of this wear, many raise drills have the drive stems replaceably mounted on the bit body, thereby extending the useful life of the bit. Addi-tionally, an elastomeric shock element may be added for absorbing the impact type loads passing through the drill. However, with the utilization of such a component, the drill bit body is relatively movable with respect to the drive stem. As a result, the inboard cutters, which are normally connected and anchored to the drive stem for stabilization and load bearing purposes, cannot now be anchored to the drive stem and still have the bit body flexibly mounted, The present invention obviates this inboard cutter stabilization problem by providing a central yoke extending around the drive stem which interconnects the saddles of the two innermost cutters. The primary advantage of the present invention is that any uneven loading acting on one of the inboard cutters can be transferred to the other via the central yoke.
The Present invention relates generally to raise type earth boring drills and, more particularly to such raise drills having shock elements for absorbing impact type loads passing through the drill.
During a raise drilling operation, a tremendous amount of wear and stress is imposed upon the drive stem of the raise bit. Because of this wear, many raise drills have the drive stems replaceably mounted on the bit body, thereby extending the useful life of the bit. Addi-tionally, an elastomeric shock element may be added for absorbing the impact type loads passing through the drill. However, with the utilization of such a component, the drill bit body is relatively movable with respect to the drive stem. As a result, the inboard cutters, which are normally connected and anchored to the drive stem for stabilization and load bearing purposes, cannot now be anchored to the drive stem and still have the bit body flexibly mounted, The present invention obviates this inboard cutter stabilization problem by providing a central yoke extending around the drive stem which interconnects the saddles of the two innermost cutters. The primary advantage of the present invention is that any uneven loading acting on one of the inboard cutters can be transferred to the other via the central yoke.
Description
~10770~
RAISE DRILL INN~ YOKE ~RIDGE
___ TECHNICAL FIELD
__ The present inventlon relates generally to raise type earth boring drills and, more particularly, to such raise drills having shock elements ~or absorbing im-pact type leads passing through the drill.
BACKGROUND OF PRIOR AP~T
A relatively large diameter hole may be provided between two locations in a mine by an operation com-monly re~erred to as raise drilling. A raise drillingoperation begins by drilling a small diameter pilot hole through the earth between the locations using a small diameter pilot bit. After the pilot hole is completed, the pilot bit is removed from the drill column and a large diameter raise bit is attached. The raise bit is then rotated and drawn along the pilot hole to enable the drill cutters to contact and disintegrate the earth formations surrounding the pilot hole, thereby enlarging the pilot hole to the desired size.
In an exemplary embodiment, the pilot hole may be 11 inches in diameter and the reamed cut hole may be six feet in diameter.
During a raise drilling operation, a tremendous amount of wear and stress is imposed upon the raise bit.
The drive stem in particular is sub~ected to consider~
able wear due to abrasive contact with the surrounding earth formation and is also subject to considerable stress resulting ~rom (a) tension due to the pulling force imparted to the drill, (b) twisting due to the ~ torque applied to the drill, and (c) bending due to :, - . ~. ~ . ... .
1~701~:~
uneven loading around the circumference of the drill.
Because of this considerable wear, many raise drills have the drive stems replaceably mounted on the bit body, thereby extending the useful life of the bit. The low profile of the separated components allows the raise bit to be trans-ported through small drifts or passages.
The disadvantage of the replaceable drive stem is that a certain amount of down time is still required to remove and replace the stem. This non-operating time is costly and it is still preferable to obtain as long a running time as possible for each bit-stem combination.
As a result other features have been incorporated into the raise drill which have prolonged the operating life of such drills. One such feature has been the addition of r an elastomeric shock element for absorbing the impact type loads passing through the drill. However, with the utiliza-tion of such a component, the drill bit body is relatively movable with respect to the drive stem. As a result, the inboard cutters, which are normally connected and anchored to the drive stem for stabilization and load bearing purposes, cannot now be anchored to the drive stem and still have the bit body flexibly mounted.
BRIEF SUMMARY OF IN~ENTION
The present invention obviates this inboard cutter stabilization problem by providing an improved raise drill of the type having a drive stem connected to a drill string for driving the cutter assembly of a raise bit. A bit body having a plurality of rolling cutter assemblies mounted thereon is a radially spaced relationship is provided, at least two of the cutter assemblies being inboard of the ~ 2-~0770~9 other cutter assemblies. The inboard cutter assemblies are interconnected by a member extending around the drive system for distributing the loads acting thereon.
In a preferred embodiment of the invention, each roller cutter assembly comprises a saddle mounted on the bit body, the saddle having a pair of yokes extending upwardly for rotatively supporting a rolling cutter. The load dis-tribution member interconnects the saddles supporting the inboàrd cutters.
The load distribution member may comprise a bridge member having a hollow cylindrical opening slightly larger than the diameter of ~he drive stem, the opening extending around the drive stem.
The bridge member may comprise two parts separable through the opening, and may form a portion of the innermost yokes supporting the inboard cutters or may be separable ` from the remaining portions of said innermost yokes.
If desired, packing material may be located within the opening and around the drive stem.
Shock absorb;ng members may be interconnected between the drive stem and the absorbing member enabling the bit body to be relatively movable with respect to the drive stem~
BRIEF DESCRIPTION OF DRAWINGS
-FIGURE 1 is a section view of a raise bit having an inner yoke bridge in accordance with the present inven-tion;
FIGURE 2 is a fragmentary plan view, partially in section of the inner yoke bridge of the present invention;
and ,~, ~;
~t~
. .
~,` '"' ' '" .
io770~s FIGURE 3 is an elevational view of an ;nboard cutter mounting arrangement.
DETAILED DESCRIPTION OF INVENTION
Referring now to the drawings, FIGURES 1 and 2 illustrate a raise drill generally indicated by arrow 10, comprising a drive stem 11, a thrust plate 12, and a bit body 13. The upper end of the drive stem 11 is provided with a tapered thread (not shown) which is adapted to be r threaded into a standard drill string through which the raise drill 10 is driven.
The thrust plate 12 has a central opening 14 which has a diameter only slightly larger than the central shank portion 15 of the drive stem 11. The central shank portion 15 is of a smaller diameter than the lower end 16 of the drive stem 11~ forming an upwardly facing peripheral shoul-der 17, against which the margin of the hole 14 in the thrust plate 12 fits when the thrust plate 12 is in the assembled position with the drive stem 11.
The drive~stem ll is removably attached to the raise drill assembly by means of the following assembly.
The attaching assembly includes a cylindrical collar 18 which extends below the thrust plate 12 and is at-tached thereto. An annular plate 19 is located inside the collar 18 and is attached to the interior walls thereof. The annular plate 19 inclùdes a central open-ing 21 which extends about the lower shank portion 16 ~`
of the drive stem 11. The annular plate 19 further in-,.~ .
1{~7 ~'01~
~ ;
cludes a plurality of threaded bores 22 clrcumferenti-ally positioned about the central opening 21. The lower shank portion 16 further includes a plurality of tapered flat surfaces 23 located about the periphery of the bottom end thereof.
A plurality of wedge blocks 24 are provided with each wedge block 24 having a bore extending there-through for receiving a threaded bolt 25. The bolts 25 are adapted to be attached to the threaded bores 22 located on the annular plate 19. Each wedge block 24 further includes a first inwardly facin~ tapered sur-face 26 for engagement with the respective flat sur~ace 23 of the drive stem 11. Each wedge block 24 further includes a second outwardly facing tapered surface 27, diametrically opposed to the first tapered surface 26.
The second tapered surface 27 is adapted to engage a - tapered surface 2% of a registering block 29 which is positioned within the collar 13 adjacent a respective wedge block 24. The blocks 29 are integrally attached to the collar 18 and ann~alar plate 19.
The bit body 13 further includes a central opening 31 which extends around the central shaft portion 15 of the drive stem 11. An annular packing member 32 is located between the central opening 31 and the central shaft portion 15.
The thrust plate 12 and the bit body 13 are interconnected by means of an elastomeric element gen-erally indicated by arrow 40. The elastomeric element 40 comprises a substantially toroidal element 42 co axially positioned with respect to the drive stem 11.
The toroidal element 42 is made of a polyurathane material which is sandwiched between a pair of plates 43 and 44 which are of a similar toroidal configura-tion. The toroidal element 42 is of polyurathane material which is bonded to the plates 43 and 44 to form an integral unit. The toroidal configuration of elements 42 and plates 43 and 44 are divided into four equal 90 segments. The plates 43 and 44 include a plurality of threaded bore holes ~hich are adapted .
- :.- . . : ,- ~ .
. . ~ ~' - ' ~ :' 1~)'77019 to receive a plurality of bolts ~l5 for connection to the thrust plate 12 and the bit body 13.
The bit body is comprised mainly of a pair of parallel plates 51 and 52 rigiclly secured to each other 5 by a plurality of ribs 5~ to form a frame. The upper plate 51 has a plurality of saddles 54 integrally mounted thereon ~or rotatively sup~orting a plurality of rolling cutters 55. In accordance to the present invention, the two innermost cutters are interconnected by means of an inner yoke bridge, generally indicated by arrow 60, which extends around the central shaft portion 56.
As shown in FIGURES 2 and ~, the inner yoke bridge 60 is made of two parts with each part ~orming 15 the innermost bearing support 61 for the cutter 55 and is attachably mounted onto the base of the saddle 54 by means of a bolt connection 62. In a similar manner, the outermost bearing support 63 for each cutter 55 is also attachably mounted on the base of the saddle 54 20 by means of a bolt connection 65, thereby forming a three part saddle comprised of elements 54, 61 and 63.
As more clearly shown in FIGURE 2, each part 61 of the inner bridge yoke 60 extending away from the cutter 55 extends around the central sha~t portion 56 of the 25 drive stem 11 and mates with adjoining ~aces. These two elements 61 are then interconnected by means of a pair of bolt connections 66.
A clearance is provided between the inner annu-lar face o~ the yolce bridge 60 and the drive stem 11.
~ Such clearance can be used as a gap or else as a means for housing an elastomeric packing 67 being connected thereto.
STATEMENT OF INDUSTRIAL _P LICATION
The raise drill 10 is utilized in a raise drill--35 ing operation to provide a relatively large diameterhole between two levels in a mine. The raise drilling operation begins by drilling a small diameter pilot hole through the earth from a first location to an open-ing at a second location, using a small diameter pilot ` 1077~D19 bit. After the pilot hole is completed, the pilot bit is removed from the drill column and the raise bit 10 is attached to the drill collar. The raise bit 10 is rotated and drawn along the pilot hole to enable the cutters 55 to contact and disintegrate the earth forma-tions surrounding the pilot hole, thereby enlarging the pilot hole to the desired si~e.
The raise bit 10 may be transported through small drifts or passages by removing the drive stem 11 and transporting the drive stem 11 and the raise bit body 13 through the small drifts or passages separately.
In removing the drive stem 11, the yoke connection 60 is first removed. Afterwards, the bolts 25 are removed utilizing conventional torque tools. Upon removal of the bolts 25 and wedge blocks 24, the drive stem 11 is lowered through the central openings of the thrust plate 12 and the bit body 13 out of engagement therewith.
The separate elements of the raise bit 10 may then be transported separately through the small drifts or pass-ages.
When the raise bit 10 is to be connected to thedrill column, the drill stem 11 is inserted through the central openings 14 and 21, respectively, until the shoulder 17 engages the margin of the thrust plate 12 around the central opening 14.
The wedge blocks 24 are then positioned as shown in the drawing and the bolts 25 are then threaded into eng~agement with the plate 19 to urge the wedge blocl~s 24 into engagement with the flat tapered surfaces 26 of the drive stem 11 and the tapered surfaces 2~ of the blocks 2~. me bolts 25 are tightened individually to enable the wedge components to be properly aligned.
Upon tightening of the bolts 25 and installing the yoL~e connection 60, the raise bit is then ready for opera-tion.
The elastomeric element 40 is interconnectedbetween the thrust plate 12 and the bit body 13 to ab-sorb the bending forces due to the unequal loading around the circumference of the drill. The elastomeric element : : .
,: ' ... .-. ~ ., :
~0'7~7019 40 is also designed to transmit all of the thrust and torsional loads from the drill stem 11 to the raise bit ~dy 13. The vertical thrust from the drill stem 11 is transmitted to the thrust plate 12 by the shoulder connection 17 and then through the elastomeric element 40 to the bit body 13. The torque is transmitted ~rom the drill stem 11 through the connection assembly to the collar 18 and the thrust plate 12 which is inte-grally connectecl thereto. The torque is then trans-mitted through the elastomeric element 40 to the bitbody 13.
In accordance with the present invention, the inner yoke bridge 60 functions to stabilize the forces acting on the inboard cutters 55 by transferring any uneven or bending loads action on one inboard cutter to the other.
The two elements 61 are separable by removing the bolts 66 and are removable from the rest of the cutter saddle construction by removing the bolts 62.
The inner yoke bridge 60 also enables the bit body 13 to be relatively movable with respect to the drive stem 11 since the bridge 60 is not anchored to the drive stem 11. However, the bridge 60 still en-ables the inboard cutters 55 to be stabilized in sub-stantially the same manner.
It should be noted that various modifications can be made to the assembly while still remaining with-in the purview of the following claims.
: :
RAISE DRILL INN~ YOKE ~RIDGE
___ TECHNICAL FIELD
__ The present inventlon relates generally to raise type earth boring drills and, more particularly, to such raise drills having shock elements ~or absorbing im-pact type leads passing through the drill.
BACKGROUND OF PRIOR AP~T
A relatively large diameter hole may be provided between two locations in a mine by an operation com-monly re~erred to as raise drilling. A raise drillingoperation begins by drilling a small diameter pilot hole through the earth between the locations using a small diameter pilot bit. After the pilot hole is completed, the pilot bit is removed from the drill column and a large diameter raise bit is attached. The raise bit is then rotated and drawn along the pilot hole to enable the drill cutters to contact and disintegrate the earth formations surrounding the pilot hole, thereby enlarging the pilot hole to the desired size.
In an exemplary embodiment, the pilot hole may be 11 inches in diameter and the reamed cut hole may be six feet in diameter.
During a raise drilling operation, a tremendous amount of wear and stress is imposed upon the raise bit.
The drive stem in particular is sub~ected to consider~
able wear due to abrasive contact with the surrounding earth formation and is also subject to considerable stress resulting ~rom (a) tension due to the pulling force imparted to the drill, (b) twisting due to the ~ torque applied to the drill, and (c) bending due to :, - . ~. ~ . ... .
1~701~:~
uneven loading around the circumference of the drill.
Because of this considerable wear, many raise drills have the drive stems replaceably mounted on the bit body, thereby extending the useful life of the bit. The low profile of the separated components allows the raise bit to be trans-ported through small drifts or passages.
The disadvantage of the replaceable drive stem is that a certain amount of down time is still required to remove and replace the stem. This non-operating time is costly and it is still preferable to obtain as long a running time as possible for each bit-stem combination.
As a result other features have been incorporated into the raise drill which have prolonged the operating life of such drills. One such feature has been the addition of r an elastomeric shock element for absorbing the impact type loads passing through the drill. However, with the utiliza-tion of such a component, the drill bit body is relatively movable with respect to the drive stem. As a result, the inboard cutters, which are normally connected and anchored to the drive stem for stabilization and load bearing purposes, cannot now be anchored to the drive stem and still have the bit body flexibly mounted.
BRIEF SUMMARY OF IN~ENTION
The present invention obviates this inboard cutter stabilization problem by providing an improved raise drill of the type having a drive stem connected to a drill string for driving the cutter assembly of a raise bit. A bit body having a plurality of rolling cutter assemblies mounted thereon is a radially spaced relationship is provided, at least two of the cutter assemblies being inboard of the ~ 2-~0770~9 other cutter assemblies. The inboard cutter assemblies are interconnected by a member extending around the drive system for distributing the loads acting thereon.
In a preferred embodiment of the invention, each roller cutter assembly comprises a saddle mounted on the bit body, the saddle having a pair of yokes extending upwardly for rotatively supporting a rolling cutter. The load dis-tribution member interconnects the saddles supporting the inboàrd cutters.
The load distribution member may comprise a bridge member having a hollow cylindrical opening slightly larger than the diameter of ~he drive stem, the opening extending around the drive stem.
The bridge member may comprise two parts separable through the opening, and may form a portion of the innermost yokes supporting the inboard cutters or may be separable ` from the remaining portions of said innermost yokes.
If desired, packing material may be located within the opening and around the drive stem.
Shock absorb;ng members may be interconnected between the drive stem and the absorbing member enabling the bit body to be relatively movable with respect to the drive stem~
BRIEF DESCRIPTION OF DRAWINGS
-FIGURE 1 is a section view of a raise bit having an inner yoke bridge in accordance with the present inven-tion;
FIGURE 2 is a fragmentary plan view, partially in section of the inner yoke bridge of the present invention;
and ,~, ~;
~t~
. .
~,` '"' ' '" .
io770~s FIGURE 3 is an elevational view of an ;nboard cutter mounting arrangement.
DETAILED DESCRIPTION OF INVENTION
Referring now to the drawings, FIGURES 1 and 2 illustrate a raise drill generally indicated by arrow 10, comprising a drive stem 11, a thrust plate 12, and a bit body 13. The upper end of the drive stem 11 is provided with a tapered thread (not shown) which is adapted to be r threaded into a standard drill string through which the raise drill 10 is driven.
The thrust plate 12 has a central opening 14 which has a diameter only slightly larger than the central shank portion 15 of the drive stem 11. The central shank portion 15 is of a smaller diameter than the lower end 16 of the drive stem 11~ forming an upwardly facing peripheral shoul-der 17, against which the margin of the hole 14 in the thrust plate 12 fits when the thrust plate 12 is in the assembled position with the drive stem 11.
The drive~stem ll is removably attached to the raise drill assembly by means of the following assembly.
The attaching assembly includes a cylindrical collar 18 which extends below the thrust plate 12 and is at-tached thereto. An annular plate 19 is located inside the collar 18 and is attached to the interior walls thereof. The annular plate 19 inclùdes a central open-ing 21 which extends about the lower shank portion 16 ~`
of the drive stem 11. The annular plate 19 further in-,.~ .
1{~7 ~'01~
~ ;
cludes a plurality of threaded bores 22 clrcumferenti-ally positioned about the central opening 21. The lower shank portion 16 further includes a plurality of tapered flat surfaces 23 located about the periphery of the bottom end thereof.
A plurality of wedge blocks 24 are provided with each wedge block 24 having a bore extending there-through for receiving a threaded bolt 25. The bolts 25 are adapted to be attached to the threaded bores 22 located on the annular plate 19. Each wedge block 24 further includes a first inwardly facin~ tapered sur-face 26 for engagement with the respective flat sur~ace 23 of the drive stem 11. Each wedge block 24 further includes a second outwardly facing tapered surface 27, diametrically opposed to the first tapered surface 26.
The second tapered surface 27 is adapted to engage a - tapered surface 2% of a registering block 29 which is positioned within the collar 13 adjacent a respective wedge block 24. The blocks 29 are integrally attached to the collar 18 and ann~alar plate 19.
The bit body 13 further includes a central opening 31 which extends around the central shaft portion 15 of the drive stem 11. An annular packing member 32 is located between the central opening 31 and the central shaft portion 15.
The thrust plate 12 and the bit body 13 are interconnected by means of an elastomeric element gen-erally indicated by arrow 40. The elastomeric element 40 comprises a substantially toroidal element 42 co axially positioned with respect to the drive stem 11.
The toroidal element 42 is made of a polyurathane material which is sandwiched between a pair of plates 43 and 44 which are of a similar toroidal configura-tion. The toroidal element 42 is of polyurathane material which is bonded to the plates 43 and 44 to form an integral unit. The toroidal configuration of elements 42 and plates 43 and 44 are divided into four equal 90 segments. The plates 43 and 44 include a plurality of threaded bore holes ~hich are adapted .
- :.- . . : ,- ~ .
. . ~ ~' - ' ~ :' 1~)'77019 to receive a plurality of bolts ~l5 for connection to the thrust plate 12 and the bit body 13.
The bit body is comprised mainly of a pair of parallel plates 51 and 52 rigiclly secured to each other 5 by a plurality of ribs 5~ to form a frame. The upper plate 51 has a plurality of saddles 54 integrally mounted thereon ~or rotatively sup~orting a plurality of rolling cutters 55. In accordance to the present invention, the two innermost cutters are interconnected by means of an inner yoke bridge, generally indicated by arrow 60, which extends around the central shaft portion 56.
As shown in FIGURES 2 and ~, the inner yoke bridge 60 is made of two parts with each part ~orming 15 the innermost bearing support 61 for the cutter 55 and is attachably mounted onto the base of the saddle 54 by means of a bolt connection 62. In a similar manner, the outermost bearing support 63 for each cutter 55 is also attachably mounted on the base of the saddle 54 20 by means of a bolt connection 65, thereby forming a three part saddle comprised of elements 54, 61 and 63.
As more clearly shown in FIGURE 2, each part 61 of the inner bridge yoke 60 extending away from the cutter 55 extends around the central sha~t portion 56 of the 25 drive stem 11 and mates with adjoining ~aces. These two elements 61 are then interconnected by means of a pair of bolt connections 66.
A clearance is provided between the inner annu-lar face o~ the yolce bridge 60 and the drive stem 11.
~ Such clearance can be used as a gap or else as a means for housing an elastomeric packing 67 being connected thereto.
STATEMENT OF INDUSTRIAL _P LICATION
The raise drill 10 is utilized in a raise drill--35 ing operation to provide a relatively large diameterhole between two levels in a mine. The raise drilling operation begins by drilling a small diameter pilot hole through the earth from a first location to an open-ing at a second location, using a small diameter pilot ` 1077~D19 bit. After the pilot hole is completed, the pilot bit is removed from the drill column and the raise bit 10 is attached to the drill collar. The raise bit 10 is rotated and drawn along the pilot hole to enable the cutters 55 to contact and disintegrate the earth forma-tions surrounding the pilot hole, thereby enlarging the pilot hole to the desired si~e.
The raise bit 10 may be transported through small drifts or passages by removing the drive stem 11 and transporting the drive stem 11 and the raise bit body 13 through the small drifts or passages separately.
In removing the drive stem 11, the yoke connection 60 is first removed. Afterwards, the bolts 25 are removed utilizing conventional torque tools. Upon removal of the bolts 25 and wedge blocks 24, the drive stem 11 is lowered through the central openings of the thrust plate 12 and the bit body 13 out of engagement therewith.
The separate elements of the raise bit 10 may then be transported separately through the small drifts or pass-ages.
When the raise bit 10 is to be connected to thedrill column, the drill stem 11 is inserted through the central openings 14 and 21, respectively, until the shoulder 17 engages the margin of the thrust plate 12 around the central opening 14.
The wedge blocks 24 are then positioned as shown in the drawing and the bolts 25 are then threaded into eng~agement with the plate 19 to urge the wedge blocl~s 24 into engagement with the flat tapered surfaces 26 of the drive stem 11 and the tapered surfaces 2~ of the blocks 2~. me bolts 25 are tightened individually to enable the wedge components to be properly aligned.
Upon tightening of the bolts 25 and installing the yoL~e connection 60, the raise bit is then ready for opera-tion.
The elastomeric element 40 is interconnectedbetween the thrust plate 12 and the bit body 13 to ab-sorb the bending forces due to the unequal loading around the circumference of the drill. The elastomeric element : : .
,: ' ... .-. ~ ., :
~0'7~7019 40 is also designed to transmit all of the thrust and torsional loads from the drill stem 11 to the raise bit ~dy 13. The vertical thrust from the drill stem 11 is transmitted to the thrust plate 12 by the shoulder connection 17 and then through the elastomeric element 40 to the bit body 13. The torque is transmitted ~rom the drill stem 11 through the connection assembly to the collar 18 and the thrust plate 12 which is inte-grally connectecl thereto. The torque is then trans-mitted through the elastomeric element 40 to the bitbody 13.
In accordance with the present invention, the inner yoke bridge 60 functions to stabilize the forces acting on the inboard cutters 55 by transferring any uneven or bending loads action on one inboard cutter to the other.
The two elements 61 are separable by removing the bolts 66 and are removable from the rest of the cutter saddle construction by removing the bolts 62.
The inner yoke bridge 60 also enables the bit body 13 to be relatively movable with respect to the drive stem 11 since the bridge 60 is not anchored to the drive stem 11. However, the bridge 60 still en-ables the inboard cutters 55 to be stabilized in sub-stantially the same manner.
It should be noted that various modifications can be made to the assembly while still remaining with-in the purview of the following claims.
: :
Claims (8)
1. A raise drill comprising: a drive stem having means at one end thereof for connecting to a drill string, a bit body having a plurality of rolling cutter assemblies mounted thereon in a radially spaced relationship, at least two of the cutter assemblies being located inboard of the other cutter assemblies and means extending around said drive stem for interconnecting said inboard cutter assemblies and distributing the loads acting thereon.
2. The raise drill as claimed in Claim 1, wherein each roller cutter assembly comprises a saddle mounted on said bit body, said saddle having a pair of yokes extending upwardly for rotatively supporting a rolling cutter, said load distribution means inter-connecting the saddles supporting said inboard cutters.
3. The raise drill as claimed in Claim 2, wherein said load distribution means comprises a bridge member having a hollow cylindrical opening slightly larger than the diameter of said drive stem, said opening extending around said drive stem.
4. The raise drill as claimed in Claim 3, wherein said bridge member comprises two parts separable through said opening.
5. The raise drill as claimed in Claim 3, wherein said bridge member forms a portion of the innermost yokes supporting the inboard cutters.
6. The raise drill as claimed in Claim 5, wherein said bridge member is separable from the remaining portions of said inner-most yokes.
7. The raise drill as claimed in Claim 3, wherein said bridge member further includes packing material located within said opening and around said drive stem.
8. The raise drill as claimed in Claim 1, further comprising shock absorbing means interconnected between said drive stem and said bit body for absorbing the impact loads therebetween, said shock absorbing means enabling said bit body to be relatively movable with respect to said drive stem.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US05/844,694 US4142593A (en) | 1977-10-25 | 1977-10-25 | Raise drill inner yoke bridge |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1077019A true CA1077019A (en) | 1980-05-06 |
Family
ID=25293401
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA310,322A Expired CA1077019A (en) | 1977-10-25 | 1978-08-30 | Raise drill inner yoke bridge |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US4142593A (en) |
| AU (1) | AU517110B2 (en) |
| CA (1) | CA1077019A (en) |
| ZA (1) | ZA785049B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4195701A (en) * | 1978-07-24 | 1980-04-01 | Smith International, Inc. | Raise drill having water passages directed toward the roller cutters |
| US4244433A (en) * | 1978-12-26 | 1981-01-13 | Smith International, Inc. | Safety mechanism for a raise drill |
| US4381038A (en) * | 1980-11-21 | 1983-04-26 | The Robbins Company | Raise bit with cutters stepped in a spiral and flywheel |
| CN104074464B (en) * | 2014-07-17 | 2016-09-07 | 徐州工程学院 | Super large caliber rig discharging machine header structure |
| CN109339708B (en) * | 2018-10-29 | 2020-05-15 | 武大巨成结构股份有限公司 | Hole forming process of anchoring hole bottom reaming device |
| CN114165173B (en) * | 2021-12-14 | 2023-07-25 | 江苏和信石油机械有限公司 | Quick assembly type drill rod and drill bit structure for rescue |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3221619A (en) * | 1960-09-02 | 1965-12-07 | Arnel T Erickson | Rotating roller machine |
| US3451722A (en) * | 1966-04-11 | 1969-06-24 | S & M Constructors Inc | Resilient mounted cutter head for tunneling machine |
| US3750767A (en) * | 1971-05-24 | 1973-08-07 | Hughes Tool Co | Rolling cutter mounting in big hole reaming bit |
| US3921734A (en) * | 1972-10-17 | 1975-11-25 | Kennametal Inc | Raise boring head and rolling cutter arrangement therefor |
| SE390188C (en) * | 1973-12-03 | 1979-10-08 | Sandvik Ab | DRILLING ROD FOR STRIKING MOUNTAIN DRILLING |
| US3920089A (en) * | 1974-03-07 | 1975-11-18 | Dresser Ind | Removable stem for raise bit |
-
1977
- 1977-10-25 US US05/844,694 patent/US4142593A/en not_active Expired - Lifetime
-
1978
- 1978-08-30 CA CA310,322A patent/CA1077019A/en not_active Expired
- 1978-09-06 ZA ZA00785049A patent/ZA785049B/en unknown
- 1978-09-07 AU AU39660/78A patent/AU517110B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| US4142593A (en) | 1979-03-06 |
| ZA785049B (en) | 1979-08-29 |
| AU3966078A (en) | 1980-03-13 |
| AU517110B2 (en) | 1981-07-09 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |